Process of purifying precipitates.



HERBERT H. DOW, OF MIllLAllD, MICHIGAN, AND WALTER S. GATES, OF WORTHINGTON. ONTARIO, CANADA, ASSIGNORS TO THE ONTARIO NICKEL COMPANY, LIMITED, OF WORTH- INGTON, CANADA, A CORPORATION'OFCANADA." i t raoonss F PurtIFYi-NG. rnEcIPrrA-res.

Be it known that we, HEiiBE'n'rI I; Dow

and W LTER'S, GATES, both citizens of the v Wo'rthi'n;gton,.District of Algoma, and Pront- ,ince of Ontario, Canada, respectively, have i of the invention- United States, residents of Midland; county of; Midland, and. State of Michigan, and

invented anew and useful Improvement Broces sesof Purifying, Precipitates, of which the following is: a specification, ,the principle eing herein explained, and the best mode in wh ichlweuhave contniplatedapplying thatprinciple, so'as to @distlnguish'jt from other inventions.

; Qur invention relates to processes of separating metals and especially to the se, aration 1: of the, same, each substantially free 0 all the ,lothers, when contained in a water solution.v

Y The underlying principle of operation. as wellas, in a. sense, the general courseot procedure of. the presentmethod'is closelyfre latd .to that forming the subject.matter of;

our pending application, Serial No. 300,728, fil'edfFebruary' 12,1906. Thus the improved results obtained'bythe present process are effected by reason of the same fact-which we.

have discovered and have 'utilized in such other process, namely-that when a reagent; which is capable of precipitating at least one of the metals as an insoluble compound, is added to a solution of.metalsn1'ore orless of the insoluble compounds of theother metals'are simultaneously,precipitated, de-

to be atleast achemical equivalent of-the reagent, then, the more insoluble reci itate is purified of its inclusions :of'the s i'ght yless insoluble precipitates of, the other metals. by- .,sub'jecting theoriginal solution and preci'pb tates ;to. a prolonged agitation bytmeanspf wthichthe soluble. corn )01H1(l -0f,t/h 8'm8t3;l-' I forming the more insolu 1e precipitate reacts with; the recipitates of. the pther metals, to

' form solu, l'e. compounds of said other metals and more Qf lrllQlIlSOlUblQj recipitate which Specification otLettersPatent- Patented app ication filed r tainer 6, 1e07, se'ria1u b.401,oo;

is p rti l s separatingof iron, copper andliiickel hfrom or solutions"substantially free 'of the others, when all are contained in'lthe same, original water solution. a

,We, are awarethajt: iron, copper and nickel have been taken from a water solution inthej same order and by the same reagents that We use, but we are not aware that products anywhere nearly, p ure have been obtained, in

, the mannerembodying our improved proclarge' amounts ,of theyaluable nietals" hayeheenldst in the iron prec'i itate in other processes. The fact; is-,well own that if two. metals are present in a solution, sndjone of the. metals fo'rrnsia precipitate, or an insoluble compound, more insolubleth-an the corresponding compound of the second in'etal,

amount ofxa reagent capable of throwing downthe first metal as a precipitate', then ,said. precipitate will-in anany cases carry down withit in insoluble for-m partv'of the second ,metalh This will happen 'first alused, an secondly often even if said second metalis not capable of being so prec1p1tated. .As an example of the first case, .if-la: solution drate, which 'reagen t will precipitate either metallalone, and the reagent is -'a.dded in the proper amount to recipitate-the iron, the-Iron solub e niokeL, .As an exampleof the second Case, if a solution; of iron ,and .nickel, with ammonium: chlorid present, be treated with ammonium hydrate, which reagent will piewith ammonium chlorid, and the reagent-be added, in. the proper amount toprecipitate the-iron, theiron recipitate will always carry original solution in an. amount much, greater than the iron, the iron will predominate in the precipitate",jbecause, -'ferriq hydrate is or olub t an w c s .11. ydrate- T usual way in vwhich these precipitations .add- -to the solution of iron and nickel in a befil fl the: proper amountpf reagent and and there .ish added to the solution'the proper 4 ,Ways in case thesecond metal is; also capable of being precipitated by the reagent which is of iron and nickelis treated with calcium by;

cipitateiron alone,- W hhammonium chlorid, but which .will. not precipitate nickel alone --cases,. if the niekehwere, not present in the.

.5 v each other, either in the form ofprecipitates ess.. ll ow'ever in factwe ,do'know, that vpreci itate' wil-l a ways carry downsome int dwnsomeinslolu le nickel. Inbothof'these I Would-be made in:the-laboratoryiwould be to 'cipitates but will not dissolve iron precipideal We are not aware that it has been' n that a slow subsequent action 'ispossible-b agitating-the mixture inthc presant o arr-excess of solublesa'lt of the metal the more insoluble precipitate, in

thls'case iron. I, i

It 'has always been 7 considered imp ossible ate at the iron out free of copper an nickel i 1 in fact has een considered necessa to take out the iron by means of, a weak a kali (followed by a strong alkali for the nickel) or ad the iron precipitate would'contain a very large amount' of nickel. By our irn' roved 1; niethod the iron may be recipitate b as stro anl'alkali asis use for the nicke in faet gfil three-metals,.iron, copper and nickel, 2'5 beremovedby the same reagent which befstron or weak. The old' method of Y suc apreci'pitate of the included j' such, for instance, as the urifyin'g of hydrate'of inclusion of nic el hydrate, 3o iii-Ito separate the precipitate from the solun, ,dissolye it, for instance in an'acid, and "cure recipitate with a roper amount of suit'ab e reagent,- where y again-"thrown down and containing some nickel blitnot'so much ofthe latter as besecond filtrate. 'The reason why the nickel exists inthe second filtrate in less quantities than-a does in the first is because in the acid ti'on with regard to the iron than it was in the original-solution, there bein less nickel presentjalid only'part 'of the niclrel present being thrown u it each time. Therefore a sufii- 21159 'cient nu erof-separationsin sufiiciently dito analysis and ordinarily four separations un-.

' K .der goo conditions are'sufiicient.

' Bothof our im roved processes, as ordinarily-practiced, w 'le giving practically ure products, do 'not at one time remove om "the' material. being treated all of the metal whose separation is sought, because of the tact-that the precipitateor solution as the case may be, is afterwards f a solution, or'with lprecipitate, con

t uiin'g BJIIBXOBSS of the: so uble salt of the eneral recesses, which we-need no't 63 of thef;respective metals contained therein,

' um hydrate) which will. dissolve nickel 'prd-- all the iron is fore, t, e. difierence of nickel'being left in the {a solutionit is in a'more disseminated.condi-'.

lute'solutions will accomplish a quantitative nietalnwhich is being purified. The'frst of.

and the subsequent purification or such fractional reci'pitates. Thus, in the first copper and nickel is agitated with a rea ent in amount equal to the chemical e uiva ent of the metal which it is desired to. rst separate out, or in the case in hand of the iron, such reagent being, for example, powdered limestone. The result is the almost imme-' diate precipitation of most of the iron as an some copper and nickel thrown down, as basic carbonates, A rolonged agitation of the precipitates in t e ori nal solution purifies the iron precipitate o the included co per and nickel basic carbonates because .0 the comparative solubilities of the ferric hydrate and said basic carbonates following order of insolubility: -Most1nsolubl, FeO H Less insoluble, CuCO,,.CuO,,H and CuO,H,, Leastinsoluble,NiC0,,.Ni0,lf,,and NiO,H,. The excess of iron salt in solution thus slowly dissolves, under the effect of-vigorous agitation, the copper and nickel basic carbonatecontained 1n the insoluble ferric hydrate, and. 'recipitates in turn more ferric hydrate. F dr instance, suppose the original per and nickel, then thefollowing reactions take place:

2FeCl, soaoo, 3H 0 CuCl CuO,H,+ a little NiCO. CuCl,+ a little FeCl amount 0 reagent, the ferric hydratelis found to be substantially free, of the included copper and nickel basic carbonates and the so ution is found tobe free of iron. The precipitate is se arated and washed by any convenient met od from the. copper and nickel solution, the latter going into any suitable container. This copper and nickel solution is agitated with calcium hydrate to the chemical e uivalen't of the copper. res ent, the result eing the almost imme iate grecipitation" of most of thecopper as' hyrate, which latter contains s01 e'nickel as hydrate, A prolonged agitation of this im-' pure cop er preci ltate 1n the copper and rilokel so ution w' purify said precipitate of the nickel because of the comparative solubilities of the recipitated hydrates. Y The excess of the sol i ble copper salt in the original solution thus slowly dissolves the nickel hydrate contained in the'insoluble cupric hydrate and recipitates in turn morecupric ,hydrate'. he reactions are as follows:

hydrate, but even ina dilute solution there is method un or such process a solution of iron,

according to the solution consists of the chloride of iron, cop- After a rolonged agitation with a proper" C'uCl i- NiCl +CaO H =ouo,H,+oao1,+ one promiscuous mass. Thismassof precipi- NiC a little ucl a little NiO H tateis, however, consft-iplutes in effeci ttllleuagzr tua startin oint t e rocess an s a e iQ' j so' referred to hereafteli'. Corresponding,

After a prolong d agitation with the then, to the first method of the companion 70 r0 er 'arnountof ca cium hydrate the cuprio process, the precipitates of iron, copper and lidiate is found to be substantially free of nickel are agitated in any suitab e vessel 1; e, nickel h drate and the solution is free with a solution containing a soluble iron (ii-copper. 'lhe cupric hydrate is separated salt, e. g. iron chlorid, in amountequa-l. to the and washed from the nickel solution,'the latchemical equivalent of the nickelprese'nt in 75 ten-going into any suitable container. This the solution, the result of. which is the dissonickel solution is. treated with suitable relution of. most .of the nickel with 'a conseagent, such as ,ealcium hydrate, the result uent formation of. additional precipitate. bein the almostimmediate precipitation of g prolonged agitation of the mixture will all 0 the nickel present, free from the iron effect a completion of this interchange .beand copper, without prolonged agitation, the cause of the comparative .so'lubilitiesof the reaction'being; ferric hyd'ate lpqd ktlhql-basicdcarbgnatek'ls of tco or an nic e w ic it is esire to ave zo Such first method as'above described will be solubility as that previously given; The ex- 35 seen to involve in effect the starting with a case of iron salt in solution thus slowly dissolution of all the metals, preciv itating theresolves, under theeflect of vigorous agitation,

from the less soluble metal y adding re-' the nickel basic carbonatethat is interminagent inamounte ual to. thechemi'cal equivagled with insoluble ferric hydrate, and coplent' of such meta and then purifying this per basic carbonate, and precipitates 'in turn precipitate'by agitation of the resultant mixmore ferric hydrate. For instance, suppose ture. Two other methods, or sub-processes, the original mass of precipitates consists of under. the same eneral process may betnore ferric hydrate and basic carbonates of cop er briefl' described. 'The first involves star-tand nickel, then-thefollowing reaction ta es 3 w tha solution of all the metals as before, place;

nigfiil l igi d dirig gi g eii t iii gn 5:011:1 0,,.NiO,H ilieGh 3H-,O agitated than the chemical equivalent, purifying this k c 3 i 'pl'gpcipitate by. agitation of the resultant After a prolonged agitation with ro'per a5 .nuxture and thereupon recipita'ting" the reamount of reagent the nickel ba 'c car onate 0 I maining portion of such ess soluble metalby will be'found to be substantially dissolved addition of an excess of reagent to the solu.- 'out and the solution to be practically free tion. So, too, the third involves starting 'of iron. .The precipitate is. separated and y with a;s0luti'on of all the metals, from which, washed any convenientmethod from the i 40 however, the less. soluble metal is preci inickelso ution, the latter going into any 05 i tated by adding reagent inan amount s'ufiisuitable container. This residual precipicient to'actually recipitate all of such metal, tate, which it will now be seen contains iron Y this precipitate .eing thereupon purified by and copper alone, is nextagitatedwith a soagitating thesarne in another portion'of'the lution containin soluble salts of iron added 4.5 ori inal solution. in amount ,equa to the chemical equivalent 4 lfiabompanion process to the one forming of the copper present. A, prolonged agita I the subject matter of the present ap lication 'tion of the resulting mixture will now. result hasfbecn thus ratherv fully described for the in eflecting the solution of the copper precipireason that the latter is quite closely related tate with an attendant depositlon of iron,

50 tpl the former asfwillll be seen}.1 Sue propelsis, the reaction being'as follows: I t en, consists'o t e stes. e'rei'na ter 11 r fdscribedand speeificall 'pointed' out in all; H tgfigf g ge ggrg g claimsfsuchflescription setting forth" in de- 3 2 tail certain'modes-of, carrying out the .inven- Upon separatin out the final precipitate '55 tion which, however, constitute but a part of and washing it asiefore from the co er so the various ways inwhich theprinciple of lution, ractically all the copper wil .e had the invention may be used. Such principle in ure orm'and entirel apart from the iron.

mayfbe generally characterized-as a frac t will bd understoo of. course .th'a tthe 'tional dissolutiomof precipitates of thesvpure nickel '{and cop erfsolution obtainedas '0 eralnnetals which it is desired to separate describedabove wll be treated with asuitone from the other, which precipitates are 'in-.-- able reagent such as calcium hydrate, ,'the termingled, so. as, to form a common mass. result-being the almostimme'dia 'iprecipita This process, a's'the other, involves. startingtion of the nickel or copper pre ent,- as"jthe withasolutionfof all the metals from which case may be. In the form of pure'prpcipi- 65 such metals are all precipltated together in tates they may, then be further-treatedq as than the chemical e uivalent of a solution containing soluble sa ts of the less soluble metal, agitating the resulting mixture until a correspondlng' amount of nickel is dissolved f and its place taken by iron precipitates. i The I mckel, in orden to I stantlally pure.

- tity of theoriginal precipitate.

solution after such agitation will obviously contain nothing but nickel. To the precipitate then remaining additional iron solution is added in an amount slightly in excess of that which is required as a chemical equivalent of the remaining co per and nickel, thus dissolving the balance oi the nickel as an imure solution containing also some copper.

his impure solution isthen removed and put Wit another u antity of the original precipitate which 0 course contains an excess of nickel precipitate. By agitation with such precipitate the copper in theso'lution is replaced by nickel and a pure solution of the latter is obtained. The same course of procedure is then followed-in treating the precipitate, after the removal, as above, of' the separate the copper from the iron.

The third method of se aratin iron, copper and nickel, correspon ing wit, the third method of the companion process, consists in adding to a portion of the original, or intermingled preci itate, a quantit of a solution containing so uble salts of t e iron in an amount greater than the chemicalequivalent oi. the nickel. By prolonged agitation, all the nickel will be dissolved outand with it a ortionof the cop er. From the resultant unpure solution t e copper is thereupon eliminated by agitation with a fresh'quan- The presence in the latter of an excess of nickel precipitate quickly effects a deposition of the copper, leavingthe solution of nickel sub- As before, a repetition of the stegs just outlined in connection with the residua precipitate will be effective in sepa rating thecopper from the iron.

Of course it will be remembered that .the separation takes place as .well with the salts of the other mineral acids and mixtures as it does with the chlorid solutions. a

2 In the above descri tion and the following claims we mean to me ude in the term iron the metal in both conditions of oxidation. We mean to include in the term nickel the nickel group of similar metals, viz. nickel and cobalt alone andtogether. We mean by the term prolonged agitation agitation for a length of time greater than that ordinarily, required by a c emical reagent to act on a solution which is ca able of being precipitated by it, and ma e the resultlng mlX- ture homogeneous. We mean by the term chemical equivalent of a reagen such an amount of that reagent as actually and finally enters into the reaction, since the cores of .some particles of insoluble reagent therefore, to add the reagent in a quantity in excess of that representing the theoretical chemical equivalent, We mean by the term insoluble reci itates those that are more insoluble than t e h drates of barium'and. calcium ,for instance, t ehydrates and carbon; ates of iron,e luminium, copper, nickel, etc.

If, at any, time, more of the-reagent is added than the chemical e u ivalent of the. metal to be precipitated, t e condition of ertluilibrium can be restored b the addition 0 more of the original so ution, which amounts, in effect, to the adding of the chemical equivalent. j

Our process ,does not give dilute solutions at any sta e, and yet we obtain final ure solutions 0 the iron, cop er and nicke instead of the impure products that. are obtained by resent methods,fand the basic principle 0 our process is the se aration of less soluble metal, both precipitates eing substantiall 'insolublealthough nothing is absolutely insoluble in a solvent by means of agitatin such intermingled precipitates with a so ution containing soluble salts of the less 'soiuble metaLf We do not, of course, confine ourselves to the use of wa tar as a solvent for obtaining the. original solutions. Where both or all of the metals in solution are capable of being precipitated by the reagent used, therehas been often instance, of. nickel in the ron; whereaswe cipitate entirely of the nickel by a sufficientl long and vigorous agitation. Our metho of course, works best on substances which,

dissemlnated, since, thus, infinitely great surfaces are constantly presented for solution and subsequent immediate action of the soluble'salt. v

We wish topoint out that if the addition graduall that it extends over a considerable ength 0 time duringwhich agitation is going on, this amounts in substance to adding the required amount of reagent and then subjecting the mixture to e Other modes of'a 'p ying t erprinciple of our-invention may. e emloye insteadof the oneexplained, change eing made as refollowing claims or. the e uivalents of such stated stepor steps be emp eyed.

one precipitated metal from anot er slightly 'of the required amount of reagent be made so i might not react and it would be necessary,

Hit

left and lost as much as 2% impurity, for f are able, by our method, to free the iron prcalthoughinsoluble, are colloidal and freely prolon' ed agitation. V

gards the process herein disclosed, provided the step orstepsstated by any one of'the vtainingva soluble salt of'the metal forming i We therefore particularly point out and distinctly claim as our invention I '1. In a process of 'se iaratmg one metal from'another, such meta s being in the formof precipitates diiferin slightly in their respective degrees of solu ility, the steps which consist in adding to the precipitates a solu tion. containing a soluble salt of the metal forming the less soluble precipitate in an amount'greater than the chemical equiva lent of the metal forming the more soluble precipitate 1 and then agitating the resulting mixture until such latter metal is substan tially dissolved out.

' v 2. In 'aprocess of separating one metal from another, such'metals being in the form of precipitates one of which is relatively insoluble, the steps which consist in adding to the precipitates a solution containing a soluble salt of the metal forming such relatively insoluble precipitate in' an amount greater than the chemical equivalentof the other metal; and then'agitating the resulting mix ture until such latter metal is substantially dissolved out.

' 3. In, a process of se arating one metal from another, such meta s being in the form of substantially insoluble precipitates, one

preci itate, however, being slightly less solule t an the others, the steps which consist in adding to the precipitates a solution consuph less soluble precipitate in an amount sufli'cient to actually dissolve all of the metal forming Zt'he more soluble precipitate; and

then agitating the resulting mixture until such latter metal is substantially dissolved out ,4. Ida process of se arating one metal from another, such meta s being in the form of substantially insoluble precipitates, one reci itate, "however, being slightly less soluhle t an the others, the steps which consist in adding to the recipitates'a solution of the metal forming t e less soluble precipitate in an amount sufficient to actually dissolve all of the metal forming the more soluble precipitate; and then agitating the resulting mixture until'the latter metal is substantially dissolved out. I

-5. In a process of separating one metal substantially free from another, such metals being in the form of precipitates differing slightly in their respective degrees of solubility, the steps which consist in repeating the following cycleof operations until each metal has been'suc'c'essively separated out:

adding to the precipitates a solution of a soluble salt of the metal forming the less soluble precipitate in an amount sufficient to actually dissolve all of the metal forming the more soluble precipitate; agitating the resulting mixture until such latter metal is dissolved out; and then separating the solution from the residual precipitate.

69,111 a rocess of separating one metal substantial y free from another, such metals in the form of precipitatcsdiffering being slightly lIl,' ,l3l1Ql1' respective degrees of solubility, the steps which consist in adding to the precipitates a solution containing a solublesalt of the metal forming the less soluble precipitate in an amount greater than the chemical equivalent of the metal formingthe more soluble precipitate agitating the resulting mixture until such latter metal is dissolved out;, separating the solution from the residual precipitate; and then .urifying such solution of any inclusions of the less soluble metal by agitating the same with another portion of the original precipitate. p

7, In a process of separating onelmetal substantially free from another, such metals being in the form of precipitates differing slightly intheir respective degrees of solubility, the stepswhich consist in repeating the following cycle of operations until each metal has been successively separated ,out:

addin to the precipitates a solution of a soluble sat of the metal forming theless soluble precipitate in an amount suificient to actu' allydissolve all of the metal forming the more soluble precipitate; agitating tl'ievresulting mixture unti such latter metal isdissol'ved out; separating the solution from the residual precipitate; and then purifyin such solution of-any inclusions of the less so uble metal:

'8; In a process of, separating one metal substantial y'free from another, suchmetals being in the form of precipitates differing slightly'in .their respective degrees of solubility, the-steps which consist in adding to the precipitates a solution of the metal forming a less soluble precipitate in an amount suflicient to actually dissolve the metal forming the more soluble precipitate; agitating the resulting mixture until such latter metal is dissolved out; separating the solution from the residual precipitate; purifying such solution of any inclusions of the less soluble metal by agitating the same with another portion of the original precipitatc,j and then repeating the foregoing series of' steps with such residual precipitate until all of the metals are separated.

9. In a process of separating iron and nickel in the form of precipitates difiering slightly in their respective degrees of solu hility, the steps which consist in adding to the precipitates a solution of the iron in an amount sullicientv to actually dissolve all of thenickel; and then agitating the resulting mixture until such nickel is dissolved out.

10. In a process of separating ironand nickel in the. formof precipitates differing slightly in the r respective degrees of solubility, the, steps which consist in adding to tho preci iitates a solution containing e'solu ble salt 0 the iron. in an amount sullicicnt to actually dissolve all of the nickel; agitating the resulting mixture until the nickel is substantially dissolved out separating the solu tion from the residual precipitate; and then purifying such solution of any inclusionsof o the iron. i 11. In a process ct separating iron and nickel in the form ohsubstantially insoluble precipitates, the iron precipitate, however,

eing slightl precipitate, t 9 steps which consist in adding to the. precipitates ,a solution containingv a t soluble salt of the iron in an amount greater than the hemica'l equivalent of the nickel; the resulting. mixture until the a t ms nic l d is substantially dissolved out; separating the solution from theresidual precipitate; and then urifyin such solution of any inclusions of t e'iron y agitating the same with another portion of the original precipitate.-

12. In a rocess of separating iron, cop er,

and nickel 111 the form of prchi pitates di eri sli htl in their respective degrees of soluty; suc precilpitatesbeing more soluble in the ordername the steps which consist in '25 adding to the precipitates a solution containin a soluble salt of a metal forming a less so uble precipitatein an amount greater than the chemicaLequivalcnt of the iyickel; a 1tatinithe resulting mixture until the nic el is su stantially dissolved out separating the solution from the residual precipitate, and

urify' the same of any inclusions of the esssolu 'le metals; adding to such residual precipitate a solution; containing a soluble iron salt in an amount greater than the chemical equivalent of the cop er;.' agitating the resulti stan'tia dissolved out and then-separating the final solution' and remaining precipitate and purifyingthe former.

and nickel .1n the form of prec pitates so ubihty, 1 such precipitates being more soluble in the order named, the steps which "consist inadding to the recipitat'es a solution containing a solub e iron salt in an amount reater than the chemical equivalent -'of'-t e nickel; agitating the resulting mixture until the nlckel is substantially dissolved out separating the solution from v the residual precipitate; purifying such solution by a 'tating, the same with another portion oft e original precipitate; adding to such residual precipitate a solution containing a soluble iron salt in an amount greater than the chemical equivalent of the copper;

agitatin the resulting mixture until the cop per is an stantially dissolved out; separating the final solution and remaining precipitate;

and purifyin suchfinal solution by a ltatinig the same wit another portion of suc re'si ual precipitate.

14. In a rocessof separating iron and fifii nickelinthe cm of basie-precipitatca-which less soluble than the nickel -mixture until t e copper is sub;

13.-In'a' rocess of separatin iron co r P g 5 E:

of October, 1907;

consists in adding to the precipitates a solos tion of iron salt, in an'amount greater than the chemical equivalent of the nickel; agitatin the rcsulting'mixture untili\the basic nicke precipitate is dissolved out separat 70.; ing the solution from the residual precipi:

-tate; and then purifying such solution of anyinclusions of the iron audcopper. l H 15,. In a process of separatlng iron eopper and nickel 1n the form of basic recipitates, thesteps which. consipt in addingfto the-"= precipitates a solution containing a soluble salt of one ofthe first, two metals in'an amount, reater than the chemical equiv;

8. f p cipitate i d lent of e nickel; agitating the resulting mixture until the nic solved out; separating the solution from the residual precipitate; purifying the latterof any inclusions of iron andcoppe'r; adding to such residual preci itatea solution containingla soluble iron sa tin an amount greater. than t e chemical equivalent of the -copper;' agitating the resulting mixture until the copper'precipitate is substantially disholved out; separating the final solution and remainiliqus'o precipitate; and then purifyingsuch fine ll solution of anyinclusions of the iron.

16. In a process of separating iron, copper i and nickel-in the form of ferric hydrate and nickelan copper basicwa'" carhona tes?nespectively, the steps which consist in adding to the precipitatesa solm tion containing 1ron GhlOI'ldlIl an amount;

greater thanithe hhemical equivalent of V nickel; agitating the resulting mixture until 1m I the mcke bas1c carbonate is dissolved oiihr separating the "solution of nickel chlorif;

from the residual precipitate; purityin'gsuch solution of any inclusions of iron and copper w 5 by agi t atin the same in another portion of. 1115 the ,ongina precipitates; adding to such residual precipitate a solution of iron chloridin an amount greater than the. chemical equivalent of the co per; agitating there-. sulting mixture unti I the copper basic care {1 1p bon'ate is dissolved out separating the solution of cop'per-chlorid from the remainin recipitate of ferric h dra'te; and then urn- Fyin such solution o any inclusions c the iron y'agitatingthe same with another pon- 116 tion of such resldual precipitate. l

Signed by HERBERr H. Dow, this 28 day HERBERT u. now Attested by: t

Tnos .Gnrswoan J12,

t; CARL W. BENNETT,

FRED N. Lower.

-Si ncd'by WALTER Si Germs, this of Octo er, 1907. a

WALTER S. GATES. Attested h i a G. J. rno'saclinn; A, N. Px'rnnucnn.

recipitates of 7 

